User agent parsing
useragent is a library written in golang to parse user agent strings.
Usage
First install the library with:
go get xojoc.pw/useragent
useragent is simple to use. First parse a string with useragent.Parse and then access the fields of useragent.UserAgent for the required information. Example:
see godoc for the complete documentation.
How it works?
Lasciate ogne speranza, voi ch'intrate. -Dante
Parsing user agent strings is a hell. There is no standard for user agent strings, so useragent must use some heuristics. The site http://www.useragentstring.com/ has been invaluable during development. Some relevant links are also:
- https://developer.mozilla.org/en-US/docs/Web/HTTP/Gecko_user_agent_string_reference
- https://developer.chrome.com/multidevice/user-agent
- https://developer.apple.com/library/safari/documentation/AppleApplications/Reference/SafariWebContent/OptimizingforSafarioniPhone/OptimizingforSafarioniPhone.html#//apple_ref/doc/uid/TP40006517-SW3
- http://blogs.msdn.com/b/ieinternals/archive/2013/09/21/internet-explorer-11-user-agent-string-ua-string-sniffing-compatibility-with-gecko-webkit.aspx
- http://docs.aws.amazon.com/silk/latest/developerguide/user-agent.html
for the supported user agents see:
- browsers: browser.go
- crawlers: crawler.go
If you think useragent doesn't parse correctly a particular user agent string, just open an issue :).
Why this library?
useragent doesn't just split the user agent string and look for specific strings like other parsers, but it has specific parser for the most common browsers/crawlers and falls back to a generic parser for everything else. Its main features are:
- Simple and stable API.
- High precision in detection of the most common browsers/crawlers.
- Detects mobile/tablet devices.
- OS detection.
- URL with more information about the user agent (usually it's the home page).
- Security level detection when reported by browsers.
Who?
useragent was written by Alexandru Cojocaru (http://xojoc.pw) and uses blang/semver to parse versions.
Thanks a lot to @brendanwalters (from http://pendo.io) for the contributions.
Donate!
License
useragent is released under the GPLv3 or later, see COPYING.